Database, 2018, 1–12 doi: 10.1093/database/bay074 Original article Original article HRPDviewer: human ribosome profiling data viewer Wei-Sheng Wu1,*, Yu-Xuan Jiang1, Jer-Wei Chang1, Yu-Han Chu1, Yi-Hao Chiu2, Yi-Hong Tsao2, Torbjo¨ rn E. M. Nordling3, Yan-Yuan Tseng4 and Joseph T. Tseng2,* 1Department of Electrical Engineering, 2Department of Biotechnology and Bioindustry Sciences, 3Department of Mechanical Engineering, National Cheng Kung University, No.1, University Road, Tainan City 701, Taiwan and 4Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI 48201, USA *Corresponding author: Tel: þ886 6 2757575#62426; Fax: þ886 6 2345482; Email: [email protected] Correspondence may also be addressed to Joseph T. Tseng. Tel.: þ886 6 2757575#58225; Fax: þ886 6 2345482; Email: [email protected] Citation details: Wu,W.-S., Jiang,Y.-X., Chang,J.-W. et al. HRPDviewer: human ribosome profiling data viewer. Database (2018) Vol. 2018: article ID bay074; doi:10.1093/database/bay074 Received 9 March 2018; Revised 17 June 2018; Accepted 19 June 2018 Abstract Translational regulation plays an important role in protein synthesis. Dysregulation of translation causes abnormal cell physiology and leads to diseases such as inflammatory disorders and cancers. An emerging technique, called ribosome profiling (ribo-seq), was developed to capture a snapshot of translation. It is based on deep sequencing of ribosome-protected mRNA fragments. A lot of ribo-seq data have been generated in various studies, so databases are needed for depositing and visualizing the published ribo-seq data. Nowadays, GWIPS-viz, RPFdb and TranslatomeDB are the three largest databases developed for this purpose. However, two challenges remain to be addressed. First, GWIPS-viz and RPFdb databases align the published ribo-seq data to the genome. Since ribo-seq data aim to reveal the actively translated mRNA transcripts, there are advantages of aligning ribo-req data to the transcriptome over the genome. Second, TranslatomeDB does not provide any visualization and the other two databases only pro- vide visualization of the ribo-seq data around a specific genomic location, while simulta- neous visualization of the ribo-seq data on multiple mRNA transcripts produced from the same gene or different genes is desired. To address these two challenges, we developed the Human Ribosome Profiling Data viewer (HRPDviewer). HRPDviewer (i) contains 610 published human ribo-seq datasets from Gene Expression Omnibus, (ii) aligns the ribo- seq data to the transcriptome and (iii) provides visualization of the ribo-seq data on the selected mRNA transcripts. Using HRPDviewer, researchers can compare the ribosome binding patterns of multiple mRNA transcripts from the same gene or different genes to gain an accurate understanding of protein synthesis in human cells. We believe that VC The Author(s) 2018. Published by Oxford University Press. Page 1 of 12 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. (page number not for citation purposes) Page 2 of 12 Database, Vol. 2018, Article ID bay074 HRPDviewer is a useful resource for researchers to study translational regulation in human. Database URL: http://cosbi4.ee.ncku.edu.tw/HRPDviewer/ or http://cosbi5.ee.ncku.edu.tw/ HRPDviewer/ Introduction ribosome binding sites in the 50 UTR under different cellu- How cells differ in gene and protein expression and how lar physiological conditions. These results indicate the these differences affect cellular functions are fundamental complicated translational regulation, modulating the pro- questions in biology. Traditionally, the research on the reg- tein synthesis (13,15). ulatory mechanism of eukaryotic gene expression was fo- Nowadays, a lot of ribo-seq data have been generated cused on the transcriptional control. Researchers assumed in various studies. Many tools have also been developed to that the change in mRNA expression level reflects the process users’ own ribo-seq data (16). For example, using change in protein expression level and correlates with the RiboGalaxy (17), users without bioinformatics expertise physiological function. Recent studies indicated that the can check the quality of their ribo-seq data, align their post-transcriptional regulation of gene expression (e.g. ribo-seq data to the genome or the transcriptome and visu- mRNA turnover, mRNA transport and translational con- alize the results. Using RiboTools (18), users can perform trol) also plays an important role in modulating the protein qualitative analysis (e.g. identification of translational am- expression level (1–3). Therefore, ‘the correlation between biguities and stop codon readthrough events) on their ribo- mRNA and protein expression’ became an issue of interest. seq data. Using PROTEOFORMER (19), users can identify Gygi et al. analyzed the mRNA and protein abundance in translation initiation sites (TISs) and generate a ribo-seq yeast and found that mRNA levels cannot accurately pre- derived translation product database from their ribo-seq dict protein levels (4). After that, due to the development data. A description of other tools [e.g. SORFs.org (20), of mass spectrometry techniques which made large-scale MTDR (21), SPECtre (22), TISdb (23), RiboDiff (24) and measurement of expressed cellular proteins possible (5), PUNCH-P (25)] can be seen in the review paper (16). more and more studies tried to address this issue in mam- On the other hand, several databases have been malian cell lines under different conditions and found constructed to process and store published ribo-seq data moderate or even poor correlation between mRNAs and (16). Among them, GWIPS-viz (26), PFdb (27)and their protein products (6–8). These findings indicate TranslatomeDB (28) are the three largest ones. GWIPS-viz that the translational regulation may have more profound was the first database to deposit and visualize [using UCSC impact on gene expression than originally expected. genome browser (29)] published ribo-seq data from 134 Translational regulation of mRNAs enables rapid changes studies in several model organisms (e.g. human, mouse and in protein concentrations to maintain cell homeostasis and yeast). RPFdb was constructed to deposit and visualize [us- modulate cell physiology (9). Dysfunction or dysregulation ing JBrowse (30)] published ribo-seq data from 45 studies in of the translational machinery leads to human diseases 8 species. RPFdb also provides a list of the most translated g- such as cancer, tissue hypertrophy, neurodegeneration and enes for each published ribo-seq data. TranslatomeDB (28) inflammation (10,11). collected 2435 published ribo-seq data in 13 species and An emerging technique called ribosome profiling (ribo- provided the translation ratio, elongation velocity index and seq) is a powerful tool to study translational regulation translational efficiency of each published ribo-seq data. (12). Ribo-seq can capture a snapshot of actively translated Although GWIPS-viz, RFPdb and TranslatomeDB mRNAs to provide genome-wide information on protein are useful for depositing published ribo-seq data, two synthesis in vivo. It is based on the following rationale: challenges remain to be addressed. First, GWIPS-viz and only actively translated mRNA fragments within a ribo- RFPdb align the published ribo-seq data to the genome and some survive exposure to nucleases. Deep sequencing of provide genome browsers to visualize the data. Since ribo- these ribosome-protected mRNA fragments thus reveals seq data aim to reveal the actively translated mRNA tran- the mRNAs which are actively translated by ribosomes. scripts, aligning the ribo-seq data to the transcriptome (i.e. Besides, by using appropriate inhibitors to block ribosome all mRNA transcripts in a cell) should be more biologically movement, ribo-seq can also be used to identify the trans- meaningful than aligning the ribo-seq data to the genome. lation start sites and the speed of translating ribosomes Second, TranslatomeDB does not provide any visualization (13,14). Moreover, ribo-seq revealed many different and the other two databases only visualize the ribo-seq Database, Vol. 2018, Article ID bay074 Page 3 of 12 data around a specific genomic location. Neither of them Table 1. The 610 collected ribo-seq datasets were assigned to can simultaneously visualize and compare the ribo-seq 14 research topics data on different mRNA transcripts which may come Research topic # of ribo-seq # of publications from the same gene or different genes. To address datasets these two challenges, we developed a database called Human Ribosome Profiling Data viewer (HRPDviewer). Apoptosis 6 1 HRPDviewer contains 610 published ribo-seq datasets Cancer mechanism 85 6 from 64 studies in human. Each ribo-seq dataset is aligned Cell cycle 27 4 Circadian rhythms 48 1 to the transcriptome. Users can compare and visualize the Disease 62 4 ribo-seq data mapped on different mRNAs under different microRNA regulatory effect 24 3 physiological conditions. This kind of visualization pro- Mitochondrial translation 4 1 vides novel biological insights. By viewing the ribo-seq mRNA modification 34 3 data mapped on the mRNAs of different genes, users can mTOR pathway 62 3 know which genes’ mRNAs are highly translated under a Protein stability 25 2 specific physiological condition. By viewing the ribo-seq RPF methodology 20 8 data mapped on different mRNA isoforms of the same Stress condition 139 8 Translational regulation 177 22 gene, users can know which mRNA isoforms are highly mechanism translated under a specific physiological condition. We be- Virus infection 106 6 lieve that HRPDviewer is a useful resource for studying translational regulation in human. Note that the number of data in Table 1 sums up to 819 not 610 is because the same ribo-seq data may be assigned to multiple topics. For example, SRR2052911 (6 h infection cytosol ribosome profiling Rep1) belongs to two topics: virus infection and stress condition.